Power receiving device having device discovery and power transfer capabilities

ABSTRACT

A wireless power transfer system is disclosed that includes a power station and a chargeable device. The power station transmits discovery beacons in order to detect a chargeable device within its vicinity using any available communication protocols and/or standards. Once a device is discovered, the power station can perform coil selection with the device in order to select preferred coils for power transfer. In addition, the chargeable device is capable of detecting the beacon signal and providing a response to notify the power station of its presence. The chargeable device is capable of performing its own coil selection for further optimization and includes various assistance functionality to aid a user in optimizing a connection with the power station.

BACKGROUND

Field of Invention

The disclosure relates to a wireless charging station andwirelessly-chargeable receiver and specifically to the improveddiscoverability and setup capabilities of those devices.

Related Art

Wireless power transfer stations, such as power pads, have recentlybecome known. However, their current crude designs and low efficiencymake them relatively undesired by a large amount of the population. As aresult, such power transfer stations have not gained the popularity thatwas originally expected.

Current wireless power transfer stations lack the means to quickly andefficiently connect with a nearby device. Instead, the connection setupis conventionally performed using wireless power transfer (WPT)communication protocols, which are slow and inaccurate. Therefore,charging devices on a conventional wireless power transfer station maytake several seconds to initialize. In addition, without having theability to communicate between the station and the charging device in amore robust way, the power transfer cannot be easily optimized.

Additional problems will arise when future WPT standards come into use.Conventional power transfer stations lack the ability to operate withinalternative standards, nor the ability to even detect such additionalstandards. As such, new functionality is needed to enhance theusefulness of wireless power transfer stations.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

Embodiments are described with reference to the accompanying drawings.In the drawings, like reference numbers indicate identical orfunctionally similar elements. Additionally, the left most digit(s) of areference number identifies the drawing in which the reference numberfirst appears.

FIG. 1 illustrates an exemplary wireless power transfer environment;

FIG. 2 illustrates a block diagram of an exemplary wireless powertransfer station;

FIG. 3 illustrates a block diagram of an exemplary coil module and loaddetection module;

FIG. 4A illustrates a top-down view of an exemplary chargingenvironment;

FIG. 4B illustrates a top down view of a wireless power transferenvironment;

FIG. 5 illustrates a block diagram of a display assistance subsystemthat may be included within a chargeable device;

FIGS. 6A and 6B illustrate plan views of an exemplary chargeable device;

FIG. 7 illustrates a graphical representation of an exemplary frequencyresponse of a receiver coil;

FIG. 8A illustrates a circuit diagram of an exemplary receiver that maybe included within a chargeable device;

FIG. 8B illustrates graphical representations of an input signal to thereceiver and an output digitized carrier frequency;

FIG. 9A illustrates a block diagram of an exemplary chargeable device;

FIG. 9B illustrates a high-level circuit diagram of the power logicmodule;

FIG. 10 illustrates a block diagram of an exemplary method fortransferring power from a power station to a chargeable device;

FIG. 11 illustrates a block diagram of a method for wirelessly receivingpower from a power station by a chargeable device; and

FIG. 12 illustrates a block diagram of an exemplary general purposecomputer system.

DETAILED DESCRIPTION OF THE INVENTION

The following Detailed Description refers to accompanying drawings toillustrate exemplary embodiments consistent with the disclosure.References in the Detailed Description to “one exemplary embodiment,”“an exemplary embodiment,” “an example exemplary embodiment,” etc.,indicate that the exemplary embodiment described may include aparticular feature, structure, or characteristic, but every exemplaryembodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same exemplary embodiment. Further, when a particularfeature, structure, or characteristic is described in connection with anexemplary embodiment, it is within the knowledge of those skilled in therelevant art(s) to affect such feature, structure, or characteristic inconnection with other exemplary embodiments whether or not explicitlydescribed.

The exemplary embodiments described herein are provided for illustrativepurposes, and are not limiting. Other exemplary embodiments arepossible, and modifications may be made to the exemplary embodimentswithin the spirit and scope of the disclosure. Therefore, the DetailedDescription is not meant to limit the invention. Rather, the scope ofthe invention is defined only in accordance with the following claimsand their equivalents.

Embodiments may be implemented in hardware (e.g., circuits), firmware,software, or any combination thereof. Embodiments may also beimplemented as instructions stored on a machine-readable medium, whichmay be read and executed by one or more processors. A machine-readablemedium may include any mechanism for storing or transmitting informationin a form readable by a machine (e.g., a computing device). For example,a machine-readable medium may include read only memory (ROM); randomaccess memory (RAM); magnetic disk storage media; optical storage media;flash memory devices; electrical, optical, acoustical or other forms ofpropagated signals (e.g., carrier waves, infrared signals, digitalsignals, etc.), and others. Further, firmware, software, routines,instructions may be described herein as performing certain actions.However, it should be appreciated that such descriptions are merely forconvenience and that such actions in fact results from computingdevices, processors, controllers, or other devices executing thefirmware, software, routines, instructions, etc. Further, any of theimplementation variations may be carried out by a general purposecomputer, as described below.

For purposes of this discussion, the term “module” shall be understoodto include at least one of software, firmware, and hardware (such as oneor more circuit, microchip, or device, or any combination thereof), andany combination thereof. In addition, it will be understood that eachmodule may include one, or more than one, component within an actualdevice, and each component that forms a part of the described module mayfunction either cooperatively or independently of any other componentforming a part of the module. Conversely, multiple modules describedherein may represent a single component within an actual device.Further, components within a module may be in a single device ordistributed among multiple devices in a wired or wireless manner.

The following Detailed Description of the exemplary embodiments will sofully reveal the general nature of the invention that others can, byapplying knowledge of those skilled in relevant art(s), readily modifyand/or adapt for various applications such exemplary embodiments,without undue experimentation, without departing from the spirit andscope of the disclosure. Therefore, such adaptations and modificationsare intended to be within the meaning and plurality of equivalents ofthe exemplary embodiments based upon the teaching and guidance presentedherein. It is to be understood that the phraseology or terminologyherein is for the purpose of description and not of limitation, suchthat the terminology or phraseology of the present specification is tobe interpreted by those skilled in relevant art(s) in light of theteachings herein.

Those skilled in the relevant art(s) will recognize that thisdescription may be applicable to many various charging and/orcommunication methods without departing from the spirit and scope of thepresent disclosure.

An Exemplary Wireless Power Transfer Environment

FIG. 1 illustrates an exemplary wireless power transfer environment 100.The environment 100 includes a wireless power transfer station(hereinafter “power station”) 110. The power station 110 includes atleast one coil 115 (115(1)-115(8) in the example of FIG. 1) arranged ina grid or matrix pattern. The coils send and receive signals between awirelessly-chargeable device 150. The exchanged signals can includedata, commands and/or other communications, and can be used to transferpower from the power station 110 to the device 150. In an embodiment,the power station 110 may also include an outer coil 120, discussed indetail below.

When a user of the device 150 seeks to wirelessly charge a battery orother power storage device within the device 150, the user moves thedevice 150 to be within a proximity of the power station 110. After aninitialization and setup period, the power station 110 loads powertransfer signals onto one or more of its coils 115 and transmits thosesignals to the device 150. The device receives the signals from thecoils 115 of the power station 110 and extracts power therefrom. In thismanner, the power station 110 functions as a power transmitter and thedevice 150 functions as a power receiver. In embodiments, the wirelesspower transfer is implemented as a magnetic coil-to-coil power transferusing a transmit coil and a receive coil. The transmit coil is excitedwith an AC current to produce an alternating magnetic field, thatinduces a secondary AC current in the receive coil. The secondarycurrent can then be rectified using a diode bridge so as to produce a DCvoltage that can be stored in a battery or used to power receivercircuits.

Exemplary Wireless Power Transfer Device and Functionality

FIG. 2 illustrates a block diagram of an exemplary wireless powertransfer station 200. The power station 200 includes a communicationmodule 220 and a coil driving module 230, and may represent an exemplaryembodiment of the power station 110.

The power station 200 includes a controller module 210 that controls thegeneral operation of the power station 200, including communicating withan external device, receiving signals from the coils of the powerstation 200 and causing signals to be loaded onto the coils.

The communication module 220 connected to an antenna 225 and may includeone or more wireless communication circuits, systems, and/or protocolsfor wireless communicating with other similarly-capable devices. Forexample, the communication module 220 may include any of Bluetooth,WiFi, WLAN, radio, infrared, optical, ultrasonic, NFC, and RFID, as wellas any other wireless communication capability that is now known orlater discovered, or any combination thereof (hereinafter collectivelyreferred to as “out-of-band communication protocol”).

The coil driving module 230 generates signals for transmission to theenvironment 100 via the coils and loads those signals onto the coils. Acoil module 240 includes the one or more coils and receives the signalsfrom the coil driving module 230. Using the coils, the power station 200may also be capable of communicating with other devices using WPTcommunication standards or other coil related standard such as NFC. Inorder to receive communications, or to detect coil loading information,the power station 200 includes a load detection module 250 that detectselectrical load variations among the coils, and is capable ofdetermining load characteristics of those coils.

Discovery

As previously discussed, one problem with conventional wireless powerstations is the delay before power transfer occurs. A substantialportion of this delay results from the initialization and setup periodthat may occur in conventional stations.

In order to more efficiently discover a wirelessly-chargeable devicewithin the vicinity of the power station 110, the power station 110 maytransmit a ping signal on all of its coils 115 simultaneously. Doing soincreases signal strength, and becomes easier for a nearby device 150 todetect the ping signal and respond. In an embodiment, the ping signalcan be transmitted over a subset of the coils 115 simultaneously. Thesubset of coils should include at least two coils, and all coils withinthe subset should be adjacent to at least one other coil within thesubset. In this manner, the ping signal can be transmitted withincreased signal strength, while maintain at least some of the coils 115in a power transfer or low-power state.

In an embodiment, the power station 110 transmits different ping signalsdepending on whether a receiving device has been detected. For example,prior to detection of a receiving device, the power station 110 maytransmit “short” pings. The short ping may be a reduced powerun-modulated signal in order to enable fast multimode detection by thereceiving device. The duration of the short ping can be, for example, 1msec. Intervals between short ping transmissions should be high enoughto allow for fast connection, but low enough to reduce powerconsumption. An interval of approximately 50 msec may be sufficient insome applications. When the short ping is detected by a receivingdevice, the receiving device may notify the power station 110 of itspresence through load modulation.

When the power station 110 detects a change in its load due to the loadmodulation caused by the receiving device, the power station 110 canthen switch to an “extended” ping. The extended ping should have aduration that allows for sufficient energy transfer for the receivingdevice to wake up and perform setup. The duration of the extended pingmay be 50-100 msec, for example. By switching to the extended ping onlyafter the receiving device has been detected, power can be conservedwhile still scanning the environment for devices through use of theshort ping.

In an embodiment, one or more devices may be charging on the powerstation 110. From an earlier initiation, or based on loads detected byits load detection module 250, the power station 200 should be aware ofthe coils occupied in charging the one or more charging devices.Therefore, using this information, the controller module 210 instructsthe coil driving module 230 to transmit the ping signal via one or moreof the remaining coils within the coil module 240. For example, thecontroller module 210 can instruct the coil driving module 230 totransmit the ping signal on all unused coils, or a group of the unusedcoils, as described above.

By modulating ping signals onto the coils, each of the above scenariosemploys load modulation for sending the ping. However, as analternative, the power station may employ an independent wirelesscommunication system for initiating communication with the chargingdevice. For example, in an embodiment, the controller module 210 of thepower station 200 may generate a ping signal, which it forwards to thecommunication module 220. The communication module 220 then transmitsthe ping signal via the antenna 225 into the environment 100 using oneor more of its wireless communication protocols, such as and of theout-of-band communication protocols listed above, for example. Using anout-of-band communication protocol allows for greater range. Inaddition, WPT communications may be undecipherable when the receivingdevice 150 it out of position with respect to the coils of the powerstation 110. The out-of-band communication protocol can be used inaddition to, or as an alternative to, pinging via the coils 115.

In an embodiment, the communication protocol used for discovery canchange based on one or more parameters. For example, the power station200 may select at least one of the communication module 220 or the coils115 for transmitting the ping signal depending on the time, coilposition of the coils 115 with respect to the receiving device 150,desired communication protocol, etc. During periods when the coils 115are not being used to transmit the ping signals, they can be turned offunless otherwise being utilized.

To provide an example, before a device has been detected, the powerstation 200 may utilize the communication module 220 to transmit theping in order to achieve increased range. The communication module 220can determine proximity of the receiving device 150 based on one or moreof several parameters, including signal strength, time of response, andtriangulation. When the receiving device falls within a predeterminedproximity, the power station 200 may switch to the coils 115 to combinethe ping with other preliminary setup functions performed by the coils115 (e.g., coil alignment, etc.). In this manner, the coils 115 can bekept in an idle state until the receiving device 150 is in range ofreceiving their communications. To provide another example, thecommunication module 220 could periodically be used in order to assistwith device alignment. In particular, if the receiving device 150 is notproperly aligned with one or more of the coils 115, it may be unable toreceive WPT communications. Therefore, periodically using thecommunication module 220 can assist the alignment procedure.

In an embodiment, the receiving device 150 could instead transmit anotification signal to notify the power station 200 of its presence. Forexample, a parameter, such as a user instruction, a power level of thereceiving device, etc. can cause the receiving device 150 to transmitthe ping signal to the environment. When sufficiently close the powerstation 200, this ping signal can be received by at least one of thecommunication module 200 and the coils 115. The received ping signal canbe forwarded to, and deciphered by, the controller module 210. Oncedeciphered, the controller module 210 controls at least one of thecommunication module 220 and the coils 115 to communicate with thereceiving device 150 to perform preliminary setup, etc. For example, thecontroller module 210 can cause the communication module 220 to transmitits ping signal in response. In this manner, charging can be quicklyinitiated because it is based on a demand by the receiving device 150.

Discovery in Multi-Standard Environment

In order to be adaptable to additional standards, each of the aboveconfigurations can be slightly modified so as to allow discovery ofdevices that may be in a different standard. In an embodiment, the powerstation can perform any of the above discovery techniques for multiplestandards in succession. For example, the power station 110 can transmita first standard ping signal on all coils or a group of coils, and thensubsequently transmit a second ping signal of the coils. Similarly,while some of the coils are being used for power transfer, the otherunused coils can be controlled to transmit ping signals for otherstandards.

In order to optimize discovery, the power station can adjust the pingsignals based on the popularity or expectation of the standard. Forexample, a first standard may be much more widely used in devices than asecond standard. In this scenario, the controller module 210 caninstruct the coil driving module 230 (or communication module 220) totransmit the ping signal of the first standard more often than the pingsignal of the second standard. The ratio among the ping signals can beadjusted based on popularity, based on the standards of devicesdiscovered by the power station, based on user input, or based on anyother statistically relevant information.

In another embodiment, the power station 110 can transmit a universalbeacon that can be detected among devices of all wireless power transferstandards. The universal beacon may include a universal data packet thathas its own message. The packet could include all the necessaryinformation necessary for nearby devices to assess their chargingcapabilities, such as standards supported by the power station 110. Theuniversal beacon may be transmitted to the environment 100 by the coils115 or the communication module 220.

The device 150 would be configured to recognize the universal beacon.Therefore, the device 150 could be configured to extract the informationfrom the universal beacon in order to determine its power chargingoptions. The device 150 could then emit a response signal that also hasa universal format in order to apprise the charging station of itsparameters before beginning power transfer. Alternatively, the device150 could emit the response signal using one of the available standardsidentified in the universal beacon.

Increased Communication Distance

Conventional WPT communication standards do not allow for transmittinginformation over long distances, as an extremely close proximity betweenthe communicating devices is required. Consequently, the power stationand the chargeable device are unable to communicate with each otheruntil they are nearly touching. This obviously creates a substantialdelay in the initiation of the charging of the device.

In order to allow for earlier communication between the device and thepower station, it is desirable to increase the communication distance ofthe power station. Therefore, in an embodiment, the power station 110includes an outer coil 120. The outer coil is disposed around aperimeter of the power station 110, or alternatively around a group ofcoils 115. The outer coil 120 is capable of being energized with datasignals that it transmits to the environment 100. The outer coil 120 canoperate at different frequencies, and/or protocols and may allow forinner coils to be turned off in certain situations. Due to its size,signals energized onto the outer coil 120 can travel further in theenvironment 100. Consequently, a device 150 approaching the powerstation 110 will receive the initiation signal at an earlier time, andcan begin preliminary setup with the power station 110 en route to thepower station 110.

In an embodiment, the outer coil 120 can perform the pings of theenvironment 100 in cooperation with the coils 115. For example, theouter coil 120 can transmit a long-distance ping signal to notifydevices out of range of pings transmitted by coils 115. Following thelong-distance ping, the coils 115 can transmit one or moreshort-distance pings to establish better communication with deviceswithin their range, and also to conserve power.

In an embodiment, the coils 115 can also be configured to transmit pingsignals over long distances. For example, the coil driving module 230can drive all of the coils to simultaneously transmit a high-poweredping signal. The constructive sum of the high-power pings sent from thecoils 115 will increase the transmission distance of the ping signal. Inaddition, this high-power simultaneous transmission by the coils 115 canbe performed with a low duty cycle to conserve power. The high-powerping transmission by the coils 115 can be performed in addition to, orinstead of, the long-distance ping generated by the outer coil 120.

In addition to the high-power simultaneous ping, the coil driving module230 can drive the coils 115 with a plurality of different power levelsand/or duty cycles. For example, the coil driving module 230 can drivethe coils 115 to simultaneously transmit a high-power ping signal, andthen to transmit a mid-power ping signal followed by a low-power pingsignal. Other power levels can be employed as well, until the coildriving module 230 drives the coils 115 to issue a high-power pingsignal again. In an embodiment, the high-power ping signal has a lowerduty signal than the other-power ping signals. Also, in an embodiment,the high-power ping signal is emitted with a predetermined frequency,whereas the ping signals emitted in between high-power ping signals haverandom power levels other than high-power.

Preliminary Setup

Once the device 150 has received the ping signal, the device 150 isaware of the power station 110. At this time, the device 150 can beginthe preliminary setup with the power station 110.

In an embodiment, the preliminary setup may include exchanging deviceparameters, capabilities and other information between the chargeabledevice 150 and the power station 110. For example, once the device 150has received the ping from the power station, the device 150 may make aninternal decision regarding whether to initiate the preliminary setup.This decision may be as simple as whether the power station 110 iscapable of charging the device 150 based on standards, power needs, etc.Once the device 150 has determined to continue with the preliminarysetup, the device 150 responds to the power station 110 with thenecessary information.

In an embodiment, the response can be sent to the power station usingthe same or different form of wireless communication employed by thepower station. For example, if the device 150 received the ping over WPTload modulation, the device 150 can transmit the response signal usingthe same protocol. Alternatively, a different protocol can be used. Forexample, the initial ping may made using any of the out-of-bandcommunication protocol described above. Communication between thedevices can switch to WPT either for the immediate response signal, orafter an initial setup has completed.

For example, in an embodiment, the power station 110 begins initialcommunication with the device 150 using NFC. The NFC standard includesits own field powering mechanism. Consequently, even when the device 150has not stored charge, the power extracted from the NFC initiationsignals can provide sufficient power to the device to begin the setupprocess. Once the necessary information has been exchanged, and thesetup has completed, the power station 110 and the device 150 can switchto the WPT protocol. The signals transferred in the WPT protocol canthen be used to provide power to the various components of the device150.

In the response, the device 150 can include any information that may berelevant to the charging/connection between the device 150 and the powerstation 110. For example, the device can report its model number, powertransfer standard preferences, power needs, etc. This information isreceived either at the communication module 220 or the coil module 240,depending on the transmission protocol employed by the device 150, andforwarded to the controller module 210. From this information, thecontroller module can tailor the charging characteristics employed bythe power station 200. For example, based on the model number of thedevice 150, the controller module can access stored data relating tothat model in order to optimize charging. This data may include thermalproperties, metal layouts, shielding properties and expectedinterferences, among others. This data may have many additional uses,such as improving foreign object detection, for example.

Coil Selection

After performing the preliminary setup, the device 150 will be broughtin close proximity with the power station 110. At this time, andparticularly when the device 150 has been placed on the power station110, coil selection should be performed to select the coils that havepreferred power transfer characteristics. In other words, a device mayonly overlap a small number of the available coils. Therefore, the coilsthat are successfully and efficiently transferring power to the deviceshould be selected in order to maintain efficiency and conserve power.Meanwhile, coils that are inefficiently transferring power, or nottransferring power, to the device can be placed in a low-power or offstate.

In an embodiment, the device 150 sends an “awake notification” inimmediate response to the ping received from the power station 110, andthe coil selection follows thereafter and may be combined with thepreliminary setup (particular when the preliminary setup is performedusing WPT communications). In an embodiment where another wirelesscommunication protocol is being used to communicate between the powerstation 110 and the device 150, the power station 110 can determine whento initiate the coil selection based on the RSSI (Received SignalStrength Indicator) of the signals received from the device 150.

FIG. 3 illustrates a block diagram of an exemplary coil module 340 andload detection module 350. The coil module 340 includes a plurality ofcoils 345 and may represent an exemplary embodiment of the coil module240, and the load detection module 340 includes a detector module 355and a multiplexer 357, and may represent an exemplary embodiment of theload detection module 240.

In an embodiment, once the coil selection process begins, the powerstation 110 energizes all of its coils to listen for the response signalsent from the device 150. For example, each of the coils 345 of the coilmodule 340 are capable of receiving response signals from any nearbydevice using WPT load modulation. The device emits the response, whichis detected by one or more of the coils 345. Each of the coils isconnected to the detector module 355 by the multiplexer 357. Themultiplexer 357 is an N multiplexer corresponding to the N coils 345.The response can be the detection of a load on one or more energizedcoils.

As the coils 345 are receiving the response signal from the chargeabledevice, the multiplexer 357 selects one of the coils 345 (e.g., coil 1).The detector module 355 receives the response signal received by theselected coil and forwards the signal to the controller module 210. Themultiplexer 357 subsequently selects each of the remaining coils 345,thereby allowing the response signal received by each of the remainingcoils to also be detected by the detector module and forwarded to thecontroller module 210.

After receiving the response signals from each of the coils 345, thecontroller module 210 performs signal analysis on the received signalsin order to determine coupling coefficients between each of the coils345 and the chargeable device. The signal analysis may includecalculating signal strengths, signal envelope analysis, among otheranalysis techniques. From the analysis, the controller module 210 candetermine which of the coils 345 have the preferred coupling coefficientwith the chargeable device. The controller module 210 then selects oneor more of the coils 345 based on the coupling coefficients andinstructs the coil driving module 230 to drive the selected coils totransfer power to the chargeable device.

FIG. 4A illustrates a top-down view of an exemplary charging environment400. The environment 400 includes a charging station 401 and achargeable device 403. The charging station 401 includes a plurality ofcoils 410. The exemplary charging station 401 has a matrix of 16 coils410(1)-410(16), however there may be more or fewer coils contained inthe same or different arrangement as that depicted.

Based on the placement of the device 402 on the charging station 401,certain coils 410 will have better coupling coefficients with thechargeable device 402 based on their proximity to the device 402 andtheir orientation with respect to the device. Therefore, in theexemplary environment 400 of the FIG. 4A, the controller module 210 maydetermine that coil 410(14) has the best coupling coefficient, withcoils 410(9), 410(10), and 410(13) have sufficient coupling coefficientsto warrant driving those coils for power transfer.

In an embodiment, the receiving device (such as the chargeable device402, for example) can perform the coil selection. In this instance,there is a need to distinguish the signals transmitted from thedifferent coils from each other.

In an embodiment, each of the coils transmits the signals at a slightlydifferent frequency. The receiving device will then be capable ofdistinguishing the different coils based on the differing frequencies ofthe received signals. In an embodiment, the transmitted frequencies areorthogonal to each other. The receiver device, upon receiving thetransmitted signals from the coils, performs signal analysis on thosesignals to determine the preferred coils for power transmission. Thepreferred coils may be a predetermined number of coils that provide thebest signal transmission, or any number of coils whose transmittedsignal strengths exceed a predetermined threshold.

Once the receiving device selects the preferred frequencies, the devicetransmits the selection to the charging station 401 using any availablecommunication protocol, such as WPT, or out-of-band communicationprotocol. Upon receipt of the selection signal from the chargeabledevice, the controller module 210 instructs the coil driving module 230to drive the selected coils.

In an embodiment, rather than being transmitted on differentfrequencies, the coils are driven sequentially in time. With referenceto FIG. 4A, the coil driving module 230 drives the coil 410(1) totransmit a signal to the environment. If the receiving device 402 iswithin range, it detects and performs signal analysis on the receivedsignal. Sequential signal transmissions are then made by the other coils410(2)-410(16). The receiving device 402 can then perform thedetermination of the preferred coils that has been described above withrespect to the power station 401 based on the timing with which itreceives the different signals. In an embodiment, the driving pattern ofthe coils differs depending on the proximity of the receiving device150.

The receiving device can then transmit an identification of the selectedcoils, based on the timing of the received signal, for example, back tothe power station 401 for selection.

In an embodiment, the receiving device 402 may not perform the actualcoil selection, but still assists in the selection process. For example,the receiving device 402 can perform signal analysis based on thesignals received from the power station 401 and transmit the analysisinformation back to the power station 401. Once the analysis informationhas been received, the power station 401 can utilize the analysisinformation to determine which of the coils have preferred couplingcoefficients with the receiving device 402. From the couplingcoefficients, the power station 401 can determine the preferred coilsfor transmitting power to the receiving device 402 based on, forexample, frequency or timing.

Receiving Device with Multiple Coils

In an embodiment, in addition to the power station 401 having aplurality of coils 410, the receiving device 402 can also have aplurality of coils. In this instance, in addition to performing coilselection among the coils of the power station 401, similar coilselection is also performed for the plurality of coils of the receivingdevice.

For example, when selection is performed by the power station 401, eachof the coils will receive signals transmitted from each of the receivingdevice coils. This can be performed in a sequential or simultaneousmanner in accordance with the above descriptions. The power station 401can then analyze the signals received from the chargeable device 402 inorder to select the coils of the power station 401 that are used for WPTtransmission. In addition, the power station 401 can select coils of thereceiving device 402. Alternatively, once the power station selects itsown preferred coils, it can transmit signals to the receiving device 402for the receiving device to select its preferred coils.

Coil Selection with Multiple Devices

FIG. 4B illustrates a top down view of a wireless power transferenvironment 400. The environment 400 includes the power station 401,first device 402, and second device 403.

In an embodiment, the first device 402 is in communication with thepower station 401 at the time the second device 403 is brought intoproximity with the power station 401. In this instance, the powerstation 401 transmits a communication to the first device 401 (eitherusing WPT or other communication protocol) informing the first devicethat coil selection will again occur.

After the power station 401 has informed the first device 402 of theimpending coil selection, the power station 401 coordinates with both ofthe first device 402 and second device 403 the coil selection process.As discussed above, coil selection can occur in the power station 401based on signals received from the first device 402 and second device403, or can occur in the first device 402 and second device 403 based onsignals received from the power station 401.

Because of the coordination required when multiple devices are presenton the power station 401, coil selection cannot solely take place withinthe individual devices. For example, if the first device 402 and thesecond device 403 select coils that are the same, coordination may beneeded to dictate whether the selected coil will communicate with thefirst device 402 or the second device 403.

In this circumstance, once the devices have selected their respectivepreferred coils, they can communicate with each other using anyavailable communication protocol in order to coordinate coil usage. Thedevices can be apprised of the communication abilities of the otherdevice based on information received from the power station, or based onscans performed of the surrounding environment.

In an embodiment, once the devices select their preferred coils, theycan forward the results to the power station 401 to make a finaldetermination. Once determined, the power station transmits thedesignations of the coils back to the devices.

The power station 401 can be configured to perform coil reselectionsafter any change to the environment, including the addition or removalof a device, the presence of foreign material, among others.

Connection Termination

As discussed above, many various communication devices and protocols maybe available to establish a connection between the power station 110 anda chargeable device 150. Similarly, these various communication devicesand protocols may be used to temporarily or permanently terminate aconnection with the device.

During communication, there may be several different reasons to suspendor terminate a connection between the power station 110 and the device150, such as for example the addition or removal of another chargeabledevice, overheating of either the device 150 or the charging pad 110,proximity of a foreign object, among others.

When one of either the power station 110 or the device 150 determinesthat communication should be severed, it communicates to the other ofsuch using any of the available communication protocols. In addition todefining the termination, the power station 110 and the device 150 canalso define a resumption of communication, if desired. In this manner,the power station 110 and the device 150 can effectively and efficientlyhandle necessary communication breaks.

Communication Diversification

During WPT communication, the device 150 may exchange communicationswith the power station 110 and/or other nearby devices. Thesecommunications may be designated for any available out-of-bandcommunication protocol. However, operating these multiple systemsconsumes significant power. Because the device 150 is already incommunication with the power station 110 through WPT, thesecommunications can be routed through the WPT protocol in order toconserve power and simplify communication.

For example, direct communications that are designated for receipt bythe power station 110 from the device 150 over a non-WPT standard cansimply be forwarded through the WPT communication protocol. This reroutecan be configured using the non-WPT communication protocol prior toimplementation. Similarly, if the device 150 seeks to communicate withanother device on or near the charging station 110 via non-WPTprotocols, the device 150 can instead send these transmissions via WPTcommunication to the power station 110. The power station 110 can thenreroute these transmissions to their designated destinations.

Exemplary Wireless Power Receiving Device and Functionality

In addition to power station, the chargeable device can also includehardware and functionality to allow for more efficient and effectivepower transfer within the power transfer environment.

Display Assistance

As discussed above, the position of the receiving device with respect tothe coils of the power station can affect the power transfer efficiencybetween them. Unfortunately, conventional chargeable devices and powerstations do not provide any means for a user to determine where tooptimally position a chargeable device.

FIG. 5 illustrates a block diagram of a display assistance subsystem 500that may be included within a chargeable device. The display assistancesubsystem includes a sensor module 510, a power receiving module 520, adisplay module 530, and a controller module 540.

The sensor module 510 includes one or more sensors to detect a spatialrelationship of the device 500 to one or more coils of the chargingstation. In other words, the sensor module 510 detects whether thedevice 500 is in a strong charging position on the charging station.This can be measured based on signal strength, signal clarity, etc.

The sensor module 510 forwards the detected information to thecontroller module 540. The controller module 540 analyzes the detectedinformation and determines a vector between a current position of thedevice 500 and a preferred location. The preferred location may be alocation at which the power transfer efficiency is expected to be at amaximum.

Once the vector has been determined, the controller module 540 controlsthe display module 530 to display the vector to a user. Based on thedisplayed information, the user can know how far, and in what direction,to move the device 500.

FIGS. 6A and 6B illustrate plan views of an exemplary chargeable device600. The vector generated by the controller module 540 includes adirection and a distance value. Therefore, the display module 530 causesa display 610 on the device 600 to display the direction 620 anddistance 630 so as to provide the user with an approximation of where tomove the device 600.

As the user moves the device, one or more sensors within the sensormodule 510 detects the movement. These sensors can include, for example,a MEMS sensor. As the device moves, the sensor module detects andforwards updated position information to the controller module 540. Thecontroller module 540 updates the vector as the device 600 moves, andcauses the display module 530 to display the updated vector to the user.

As the device 600 moves closer to its intended destination, themagnitude of the vector will continue to shrink. Once the magnitudefalls below a predetermined threshold, the controller module 540 causesthe display module 530 to display a success notification. For example,FIG. 6B illustrates the device 600 with a success notification beingdisplayed on its display 610. In an embodiment, the success notificationmay include an illustrative indicator 640 and written indicator 650. Inan embodiment, the notifications to the user, including the vector andsuccess notifications can be made using one or more indicator lights,such as an LED. The on/off frequency of the LED can be adjusted based onthe relative location of the charging device. To the preferred location.

Throughout the process of locating the device on the power station, thevarious components can be powered by the receiving module 520.Specifically, the power receiving module 520 can receive power from thepower station using load modulation, and provide the received power tothe various components. Consequently, even when the battery of thedevice is empty of charge, the device 500 can provide the visualassistance to the user.

Receiver Design

As discussed above, the power station may be configured to transmitbeacon signals at varying frequencies in order to increase devicediscovery. Therefore, it may be beneficial for a receiver within thereceiving device to be capable of receiving signals within the multiplefrequencies that may be transmitted by the power station.

Therefore, in an embodiment, the receiver includes one receiver coil foreach frequency on which the power station may transmit signals. Onereceiver coil is tuned to each of the expected frequencies in order toreceive all signals transmitted from the power station.

In another embodiment, the receiving device includes a single receivercoil. The receiver coil is initially tuned for broadband discovery, andis capable of being retuned to a particular frequency once acommunication frequency has been established.

For example, FIG. 7 illustrates a graphical representation of anexemplary frequency response of the receiver coil. During preliminarydiscovery and communication establishment, the receiver coil can betuned to a broadband reception state. The broadband frequency response701 of the coil should be such that the coil is capable of detecting atleast most of the frequencies on which the power station may transmitthe beacon signal (e.g., frequencies f₁, f_(s), f₃, f₄, and f₅).

Although the broadband configuration allows the receiver to receivemultiple different frequencies of signals, the magnitude response of thecoil in this configuration may provide less than optimal signalstrengths. Therefore, once the initial communication has beenestablished, the receiver coil can be retuned to a selected frequencyf_(s). The narrowband frequency response 702 will provide greater signalstrength of received signals, as well as filter signals and noiseoutside of the selected narrow frequency band.

Determining Frequency

As discussed above, the receiver coil can be tuned to a broadband statein order to receive signals from multiple possible transmission carrierfrequencies. However, because the broadband configuration is intended tocover multiple carrier frequencies, the receiver can include hardwareand functionality that is capable of detecting the carrier frequencyactually employed by the power station.

FIG. 8A illustrates a circuit diagram of an exemplary receiver 800 thatmay be included within the chargeable device. The receiver 800 includesa receiver coil 810, a capacitor 820, control logic 830 connected to aplurality of current control devices 850, and a receiver module 840.

In an embodiment, the receiver 800 determines the carrier frequency ofthe received signal based on an output of a diode bridge, or equivalentthereof. Specifically, the receiver coil 810 is loaded with a signalfrom the environment that includes the carrier frequency, which isfiltered by the capacitor 820. The plurality of current control devices850 are arranged in a diode bridge configuration, and can each becontrolled by control logic 830. The current control devices 850 mayinclude diodes, FETs, or other such similar devices.

The diode bridge receives the input signal, and extracts therefrom adigital representation of the carrier frequency signal. FIG. 8Billustrates graphical representations of the input signal 891 and theoutput digitized carrier frequency 892. This information is sent to thereceiver module 840, which can determine from the digitized carrierfrequency 892 the carrier frequency of the transmission sent by thepower station. Once determined, the device can retune its receiver coilto have a narrowband configuration centered at the detected carrierfrequency. The coil can be tuned by having an adjustable tap for thecoil 810, or a variable capacitor for capacitor 820 to affect theresonance of coil 810.

In an embodiment, the carrier frequency of the beacon signal transmittedby the power station can be detected based on pulse width and frequencyof the beacon signal.

Power Distribution

The exemplary chargeable device may include several power sources and inaddition to the WPT subsystem, as well as several power sinks inaddition to its charging battery. Therefore, the device may beconfigured to allow for intelligent power distribution between thesources and sinks in order to add robustness to the device.

FIG. 9A illustrates a block diagram of an exemplary chargeable device900. The chargeable device includes a receiver module 910 (e.g., whenreceiving power signals), a USB module 920, and a battery, all of whichmay act as power sources. The device also includes a main subsystemmodule 950 and a display module 960 that, in addition to the battery 940and receiver module 910 (e.g., when transmitting power signals), may actas power sinks, as described below. The device 900 also includes a powerlogic module 930 to control power distribution between the variouscomponents. Those skilled in the relevant art(s) will recognize thatmore or fewer power sinks and sources may be included within the device900 within the spirit and scope of the present disclosure.

The receiver module 910 may be capable of extracting power from receivedsignals, such as through WPT or NFC communications. The USB module 920may receive operating power from its USB connection to another deviceand the battery module 940 may provide stored power to the variouscomponents of the device 900. Therefore, the receiver module 910, theUSB module 920, and the battery module 940 can each act as a powersource. Meanwhile, the battery module 940, the main subsystem module950, the display module 960, and the receiver module 910 are all capableof consuming power based on their operating states, and therefore canall be classified as power sinks.

FIG. 9B illustrates a high-level circuit diagram of the power logicmodule 930. The power logic module includes multiplexers 931-934corresponding to each of the power sinks. Each multiplexer has inputs ofeach available power source. Because a power source is incapable ofproviding power to itself, it is considered unavailable for purposes ofits multiplexer's inputs.

Therefore, multiplexer 931 corresponding to the battery module 940 hasas its inputs the receiver module 910 and the USB module. The powerlogic module 930 is capable of detecting power sources that arecurrently providing power, and routes the received power to the powersinks that require the power. This can be done in a hierarchical mannerbased on current devices operational needs.

For example, during display assistance when charging on a power station(discussed above), the power logic module 930 receives power from thereceiver module and controls multiplexer 933 to select the receivermodule input to provide power to the display module 960. Once thedisplay assistance has completed, the power logic module 930 deselectsthe receiver module as the input to the multiplexer 933 and selects thereceiver module input to the multiplexer 931 in order to providecharging power to the battery module 940. Through monitoring andconfiguration updating, the power logic module 930 can route receivedpower to needed components within the device 900.

Cloud Based Charging Assistance

In any given environment, there may be several power stations availablefor use by a chargeable device. However, with the introduction of newand additional power transfer standards, some of these stations may beineffective for charging the device. In addition, some may requirepayment (discussed below), whereas others may be free. Many otherproperties, such as power station availability, may aid a user inselecting and locating a nearby power station for charging the user'sdevice.

In order to gain access to this information, a cloud-based system can beutilized. In the cloud-based system, devices and device users gatherinformation of the various power stations as they use or pass by thosepower stations. The devices upload the gathered information to the cloud(e.g., a server), which is then accessible by other devices. Therefore,a device seeking to use a power station for charging can access thecloud and download data relating to the environment. From the downloadedinformation, the device can select a nearby available power station thatsupports a power transfer standard supported by the device. The devicecan then navigate its user to the selected power station using GPS orother mapping techniques.

Billing

As power stations are integrated into public settings, it may becomeimportant for power suppliers to bill individuals for the use and powerconsumption of their power stations. Consequently, in an embodiment, thedevice can include payment functionality to pay for power received fromthe power station.

In an embodiment, the device acts as a prepaid card, and can be “loaded”with an amount of money defined by its user after payment has been madeto a third-party company. In an embodiment, payment can be renderedafter charging has taken place. For example, the device can upload itscredit card and authorization information to the power station prior tocharging. The power station can then charge for the power transferred tothe device after charging completes. In another embodiment, payment canbe rendered in advance and the power station will transfer an amount ofpower equivalent in value to the advance payment.

Payment information, such as account and authorization information canbe transferred using any available communication standard, includingWPT, out-of-band communication protocol, etc.

Billing for transferred power allows for many additional configurations.For example, the power station can offer premium power (e.g., fasttransferring, prioritized over other devices, etc.) at a premium costrate. In addition, wireless service providers can bundle wireless powertransfer charges into their service fees. Alternatively, the powerstation itself can provide a bundled charge to receive both power andwireless network access. In these manners, charging stations cangenerate revenue for power and other services transferred to devicesthat utilize their services.

Exemplary Method for Wirelessly Transmitting Power

FIG. 10 illustrates a block diagram of an exemplary method fortransferring power from a power station to a chargeable device.

The power station begins by transmitting a beacon signal to asurrounding environment (1010). The beacon can be transmitted atdifferent frequencies, with different duty cycles, and/or usingdifferent standards. Upon receipt of a response signal from a nearbydevice (1020), the power station initiates communication with the device(1030). The communication may include preliminary setup and can beperformed on any mutually available wireless communication protocol.

Once the preliminary setup has been performed and needed devicecharacteristics have been obtained and accounted for, the power stationbegins a coil selection process (1040). The coil selection processincludes determining a power coupling between each coil of the powerstation and each coil of the chargeable device based on signalstransmitted by the power station and/or the chargeable device.

After coil selection has concluded, the power station drives selectedcoils (determined during the coil selection process) to transmit powertransfer signals to the chargeable device (1050). In certaincircumstance, the power station may terminate power transfer (1060) tothe chargeable device. If the chargeable device remains at or near thepower station, power transfer can resume at a later time, likely afterrepeating the coil selection process (1040). Alternatively, the methodends.

Those skilled in the relevant art(s) will recognize that the abovemethod can additionally or alternatively include any of thefunctionality of the power station 110 discussed above, as well as anyof its modifications. Further, the above description of the exemplarymethod should neither be construed to limit the method nor thedescription of the mobile device power station 110.

Exemplary Method for Wirelessly Receiving Power

FIG. 11 illustrates a block diagram of a method for wirelessly receivingpower from a power station by a chargeable device.

The device begins by receiving a beacon signal from a nearby powerstation (1110). After receiving the beacon signal, the device may needto determine a frequency and/or standard associated with the beaconsignal (1120) so as to properly communicate with the power station. Ifnecessary, the device can then adjust its receiver to the determinedfrequency (1130) in order to increase communication efficiency with thepower station.

Once communication has been established, the device performs an initialcommunication with the power station (1130), which may includepreliminary setup, etc. The preliminary setup exchanges informationbetween the device and the power station that may improve efficiency oftheir power transfer link.

As the device approaches/contacts the power station, the device performscoil selection with the power station (1150). The coil selection processdetermines preferred coils from among the power stations available coilsand/or the device's coils that are to be used for power transfer. Afterthe coils have been selected, the device can begin to receive power fromthe power station (1160). This received power can then be routed,together with any power received from other power sources, to any powersink within the device requiring the power (1170).

Those skilled in the relevant art(s) will recognize that the abovemethod can additionally or alternatively include any of thefunctionality of the chargeable device 150/200/500/900 discussed above,as well as any of its modifications. Further, the above description ofthe exemplary method should neither be construed to limit the method northe description of the mobile device chargeable device 150/200/500/900.

Exemplary Computer System Implementation

It will be apparent to persons skilled in the relevant art(s) thatvarious elements and features of the present disclosure, as describedherein, can be implemented in hardware using analog and/or digitalcircuits, in software, through the execution of instructions by one ormore general purpose or special-purpose processors, or as a combinationof hardware and software.

The following description of a general purpose computer system isprovided for the sake of completeness. Embodiments of the presentdisclosure can be implemented in hardware, or as a combination ofsoftware and hardware. Consequently, embodiments of the disclosure maybe implemented in the environment of a computer system or otherprocessing system. An example of such a computer system 1200 is shown inFIG. 12. One or more of the modules depicted in the previous figures canbe at least partially implemented on one or more distinct computersystems 1200.

Computer system 1200 includes one or more processors, such as processor1204. Processor 1204 can be a special purpose or a general purposedigital signal processor. Processor 1204 is connected to a communicationinfrastructure 1202 (for example, a bus or network). Various softwareimplementations are described in terms of this exemplary computersystem. After reading this description, it will become apparent to aperson skilled in the relevant art(s) how to implement the disclosureusing other computer systems and/or computer architectures.

Computer system 1200 also includes a main memory 1206, preferably randomaccess memory (RAM), and may also include a secondary memory 1208.Secondary memory 1208 may include, for example, a hard disk drive 1210and/or a removable storage drive 1212, representing a floppy disk drive,a magnetic tape drive, an optical disk drive, or the like. Removablestorage drive 1212 reads from and/or writes to a removable storage unit1216 in a well-known manner. Removable storage unit 1216 represents afloppy disk, magnetic tape, optical disk, or the like, which is read byand written to by removable storage drive 1212. As will be appreciatedby persons skilled in the relevant art(s), removable storage unit 1216includes a computer usable storage medium having stored therein computersoftware and/or data.

In alternative implementations, secondary memory 1208 may include othersimilar means for allowing computer programs or other instructions to beloaded into computer system 1200. Such means may include, for example, aremovable storage unit 1218 and an interface 1214. Examples of suchmeans may include a program cartridge and cartridge interface (such asthat found in video game devices), a removable memory chip (such as anEPROM, or PROM) and associated socket, a thumb drive and USB port, andother removable storage units 1218 and interfaces 1214 which allowsoftware and data to be transferred from removable storage unit 1218 tocomputer system 1200.

Computer system 1200 may also include a communications interface 1220.Communications interface 1220 allows software and data to be transferredbetween computer system 1200 and external devices. Examples ofcommunications interface 1220 may include a modem, a network interface(such as an Ethernet card), a communications port, a PCMCIA slot andcard, etc. Software and data transferred via communications interface1220 are in the form of signals which may be electronic,electromagnetic, optical, or other signals capable of being received bycommunications interface 1220. These signals are provided tocommunications interface 1220 via a communications path 1222.Communications path 1222 carries signals and may be implemented usingwire or cable, fiber optics, a phone line, a cellular phone link, an RFlink and other communications channels.

As used herein, the terms “computer program medium” and “computerreadable medium” are used to generally refer to tangible storage mediasuch as removable storage units 1216 and 1218 or a hard disk installedin hard disk drive 1210. These computer program products are means forproviding software to computer system 1200.

Computer programs (also called computer control logic) are stored inmain memory 1206 and/or secondary memory 1208. Computer programs mayalso be received via communications interface 1220. Such computerprograms, when executed, enable the computer system 1200 to implementthe present disclosure as discussed herein. In particular, the computerprograms, when executed, enable processor 1204 to implement theprocesses of the present disclosure, such as any of the methodsdescribed herein. Accordingly, such computer programs representcontrollers of the computer system 1200. Where the disclosure isimplemented using software, the software may be stored in a computerprogram product and loaded into computer system 1200 using removablestorage drive 1212, interface 1214, or communications interface 1220.

In another embodiment, features of the disclosure are implementedprimarily in hardware using, for example, hardware components such asapplication-specific integrated circuits (ASICs) and gate arrays.Implementation of a hardware state machine so as to perform thefunctions described herein will also be apparent to persons skilled inthe relevant art(s).

CONCLUSION

It is to be appreciated that the Detailed Description section, and notthe Abstract section, is intended to be used to interpret the claims.The Abstract section may set forth one or more, but not all exemplaryembodiments, and thus, is not intended to limit the disclosure and theappended claims in any way.

The invention has been described above with the aid of functionalbuilding blocks illustrating the implementation of specified functionsand relationships thereof. The boundaries of these functional buildingblocks have been arbitrarily defined herein for the convenience of thedescription. Alternate boundaries may be defined so long as thespecified functions and relationships thereof are appropriatelyperformed.

It will be apparent to those skilled in the relevant art(s) that variouschanges in form and detail can be made therein without departing fromthe spirit and scope of the disclosure. Thus, the invention should notbe limited by any of the above-described exemplary embodiments, butshould be defined only in accordance with the following claims and theirequivalents.

What is claimed is:
 1. A device capable of wireless power reception in awireless power transfer (WPT) environment, the device comprising: areceiver configured to operate in a broadband mode and a narrowbandmode, the receiver being configured to receive a beacon signal from theWPT environment when in the broadband mode, wherein the beacon signalincludes data that identifies one or more WPT standards supported by anearby power station; a receiver module configured to determine acarrier frequency of the received beacon signal and to tune the receiverto the narrowband mode centered at the determined carrier frequency; atransmitter configured to transmit a notification signal via a non-WPTstandard to the WPT environment in order to notify the nearby powerstation of the presence of the device, the notification signal beingtransmitted prior to receiving the beacon signal and in response to apredetermined trigger within the device; and a coil configured to alsotransmit the notification signal to the WPT environment using WPT loadmodulation during the transmitting by the transmitter, wherein thepredetermined trigger includes at least one of a power level of thedevice falling below a predetermined threshold or a user instruction,wherein in response to the receipt of the beacon signal, the transmittertransmits a response signal to the WPT environment, and wherein theresponse signal includes at least one WPT standard supported by thedevice.
 2. The device of claim 1, wherein the beacon signal was receivedvia a non-WPT communication standard.
 3. The device of claim 1, furthercomprising a diode bridge that includes an arrangement of a plurality ofcurrent control devices, wherein the receiver module determines thecarrier frequency of the received beacon signal based on a digitizedoutput of the diode bridge.
 4. The device of claim 1, wherein in thebroadband mode, the receiver receives signals from within a broadfrequency spectrum that includes a plurality of anticipated possibletransmission carrier frequencies, and wherein in the narrowband mode,the receiver receives signals primarily at the determined carrierfrequency while filtering signals outside the immediate vicinity of thecarrier frequency.
 5. The device of claim 1, further comprising: aplurality of power sources; a plurality of power sinks; and a powerlogic module configured to route power received by the plurality ofpower sources to the plurality of power sinks based on need and priorityof the plurality of power sinks.
 6. The device of claim 5, wherein atleast one of the plurality of power sources is also a power sink.
 7. Thedevice of claim 1, wherein the beacon signal is at least one of a shortbeacon signal or a long beacon signal.
 8. The device of claim 7, whereinthe beacon signal is the short beacon signal prior to detection of thedevice, and is the long beacon signal after the detection of the device.9. The device of claim 7, wherein the short beacon signal is unmodulatedand the long beacon signal is modulated.
 10. The device of claim 7,wherein the short beacon signal is at a low power compared to the longbeacon signal.
 11. The device of claim 1, wherein the notificationsignal is transmitted to the WPT environment by a plurality of coilssimultaneously.
 12. A method of wirelessly receiving power from a powerstation by a wirelessly chargeable device, the method comprising:transmitting a notification signal via a non-wireless power transfer(WPT) standard from a wireless transmitter to the power station in orderto notify the power station of the presence of the wirelessly chargeabledevice in response to a predetermined trigger within the wirelesslychargeable device; transmitting the notification signal from a coil ofthe wirelessly chargeable device using WPT load modulation during thetransmitting from the wireless transmitter; receiving a beacon signalfrom the power station via a receiver coil tuned for broadbanddiscovery, after the transmission of the notification signal, the beaconsignal including data that identifies one or more wireless powertransfer standards supported by the power station, wherein the beaconsignal includes data that identifies one or more WPT standards supportedby the power station; determining a carrier frequency of the beaconsignal; tuning the receiver coil of the wirelessly chargeable devicebased on the determined carrier frequency of the beacon signal;transmitting a response signal to the power station in response to thebeacon signal, the response signal including characteristics and powertransfer capabilities of the wirelessly chargeable device, including atleast one WPT standard supported by the wirelessly chargeable device;and wirelessly receiving power from the power station in accordance withthe power transfer capabilities, wherein the predetermined triggerincludes at least one of a power level of the wirelessly chargeabledevice falling below a predetermined threshold or a user instruction.13. The method of claim 12, further comprising: receiving a test signalfrom the power station on a plurality of coils; determining couplingcoefficients for each of the plurality of coils based on the receivedtest signal; and identifying to the power station results of thecoupling coefficient determination.
 14. The method of claim 13, whereinthe results of the coupling coefficient determination include at leastone of a preferred coil selection and a preferred coil coupling betweenthe plurality of coils of the wirelessly chargeable device and aplurality of power station coils.
 15. The method of claim 12, whereinthe characteristics include at least one of shielding properties and ametal layout of the wirelessly chargeable device, and wherein the powertransfer capabilities include an identification of all WPT standardssupported by the wirelessly chargeable device.
 16. The method of claim12, wherein the wirelessly received power is routed, together with anypower received from other power sources, to power sinks based on needand priority of the power sinks.
 17. The method of claim 12, furthercomprising: upon a change in a number of wirelessly chargeable devicesbeing serviced by the power station: terminating wireless power transferbetween the power station and the wirelessly chargeable device;performing a coil selection procedure to obtain an updated coilselection; and wirelessly transferring power between the power stationand the wirelessly chargeable device using the updated coil selection.18. The method of claim 12, wherein the predetermined trigger is a powerlevel of the wirelessly chargeable device falling below thepredetermined threshold.
 19. The method of claim 12, wherein thepredetermined trigger is the user instruction.
 20. The method of claim12, wherein the notification signal is transmitted to the WPTenvironment by a plurality of coils simultaneously.